Multiple point lift plate



p 1968 B. H. MARSHALL 3,401,973

MULTIPLE POINT LIFT PLATE Filed Dec. 27, 1966 INVENTOR BENSON H.MARSHALL ATTORNEY United States Patent O 3,401,973 MULTIPLE POINT LIFTPLATE Benson H. Marshall, Fairfax, Va., assignor to Norwood L. Sorrell,Benson, N.C.

Filed Dec. 27, 1966, Ser. No. 605,039 2 Claims. (Cl. 294-93) ABSTRACT OFTHE DISCLOSURE I A lift plate with plural radially adjustable contactbars, the bars being adapted for positioning in such manner as to belocated below an article to be lifted.

CROSS-REFERENCES TO RELATED APPLICATIONS This application deals with thegeneral subject matter of United States application Ser. No. 593,572,filed Nov. 10, 1966, by Norwood L. Sorrell, and is primarily adapted forthe lifting of components of street access cover assemblies of the typedescribed in Sorrell application Ser. No. 498,544, filed Oct. 20, 1965,now United States Patent No. 3,331,295.

BACKGROUND OF THE INVENTION (1) Field of the invention The presentinvention pertains to a handling or hoisting implement for imparting avertical lift force to an object of the type requiring unilinearmovement to avoid damage or binding.

(2) Description of the prior art It has heretofore been known to provideextensible lift apparatus for the lifting of sewer tops and the like.Representative of the prior patents in the field is United States PatentNo. 3,206,243. In devices of that type, it is necessary that locatormeans be supplied on the article to be lifted, or that the positioningof the lift apparatus be very precise to avoid tilting during liftoperations with consequent binding or damage to the article to belifted.

SUMMARY OF THE INVENTION The instant invention provides a noncomplexmeans for vertical lifting of sewer top support walls and similararticles, the present apparatus having multiple point, extendable andretractable engagement elements insuring linear movement of the articlewithout the necessity for positioning of the elements with preformedlocators, and obviating the necessity for careful location of theelements with respect to the object to be lifted.

An important advantage of the present invention resides in the provisionof a lift apparatus for linear, vertical lifting wherein the lift primemover connector is fully effective on a single point hook-up, thusadapting the lift apparatus to use with available maintenance equipmentsuch as fork lift trucks, front end loaders, and the like. Additionalobjects of the invention include the provision of a lift with extensibleengagement means and further provided with stop lug means to securelyposition the engagement means in either extended or retracted locationsthus to prevent any danger of inadvertent disengagement during a liftoperation.

Still another objective concerns the provision of a new and novel liftbar connector having a nonrigid connection with its hoist cable to avoidshock damage to the article to be lifted, and to facilitate theconnection of the connector and the hoist.

Other and further objects and advantages of the inven tion will becomeapparent to those skilled in the art from a consideration of the drawingand specification herein below.

3,401,973 Patented Sept. 17, 1968 'BRIEF DESCRIPTION OF THE DRAWINGFIGURE 1 is a vertical cross sectional view through a lift assemblyconstructed and assembled in accordance with the teachings of theinvention, showing atypical preferred environment of use;

FIGURE 2 is a top plan view from the approximate plane of the line 2-2of FIGURE 1, looking in the direction of the arrows; and

FIGURE 3 is a view similar to FIGURE 2, showing an alternative positionof the engagement means.

DECRIPTION OF THE PREFERRED EMBODIMENT In FIGURE 1, a typicalenvironment of use is illustrated, comprising paving 10 with a topsurface 12 having an access opening 14 above a service casing 16. Acover wall 18 is imbedded in the paving and has an inward flange 20supporting a height adjustment ring 22 and service lid support wall 24.The wall 24 has in inward ledge 26 Which supports the cover (not shown)in flush relation to the surface 12.

As contemplated in the aforesaid prior application Ser. No. 498,544,when an additional layer of paving is placed upon the surface 12, it isnecessary to raise the wall 24 to supplement or replace the ring 22 withone of greater height. Thereafter, the wall 24 is replaced, thus raisingthe lid to flush relation with the new level of the paving. Lifting ofthe wall 24 must be in a vertical direction and it is necessary that thelift be unilinear in order to avoid binding resulting from anysubstantial deviation.

The present invention comprises lift apparatus 28 the basic component ofwhich is a substantially flat, round plate element 30 having an upperside 32 and lower side 34 and a circumferential edge 36. The plate has acentral opening 38 formed therein, and an elongated vertical sleeve 40is fixed therein by welding or otherwise.

Slidably positioned in the vertical sleeve 40 is a substantiallycylindrical lift rod 42 with an enlarged base 44 at its lower end and aring 46 at its upper end. FIGURE 1 shows a hoist line 48 from a liftprime mover power source having a weight 50 and a book 52 for releasableengagement with the ring 46 of the lift rod, The sliding engagement ofthe rod 42 in the sleeve 40 permits the hook to be readily engaged andalso, as indicated above, lessens the likelihood of shock damage.

In FIGURES 2 and 3, is Will be observed that a plurality of horizontal,tubular sleeve members 54 are welded on the top side 3-2 of the plate.The members 54 are radially positioned and are equidistantly spaced sothat, where three are employed as shown, they are arranged atsubstantially 120 with respect to each other. Each member 54 has aslideway 56 extending fully therethrough in a radial direction and inwhich a substantially cylindrical, solid bar 58 is slidably mounted. Thebars 58 have distal ends 60 and proximal ends 62, and right angular bars64 are bent from the ends 62.

A pair of inner and outer stop lugs 66, 68 is provided for each bar. Thelugs are fixed to the side 32 of the plate. The inner lug is laterallyelongated to prevent inward extension of the bar 58 thereby, while thelug 68 is located in such manner as to permit the bar to bypass it whenthe angle bar 64 is vertically positioned, but to prevent its passagewhen horizontal.

Referring again to FIGURE 1, it is therein to be noted that gussetplates 70 extend from the vertical sleeve 40 at locations preferablysubjacent the horizontal sleeve members 54.

In operation, the assembly 28, connected to the hoist line 48 is loweredinto the opening of the wall 24 to a age tothe wall and are hel'd'insuch position by engagement of the angle bars 60 between the lugs 66 and68 as shown in FlGURE 3. Then, the bars are extended beneath the ledgeand again engaged by horizontal positioning of the angle bars 64forwardly of the lugs 68 as shown in FIGURE 2. In such position,disengagement is virtually impossible, and replacement of the ring 22may be accomplished without difiiculty and without danger of dropping ofthe wall 24.

Having described and illustrated an embodiment ofthis invention in somedetail, it is to be understood that this description and illustrationhave been offered only byway of example, and that the invention is to belimited in scope only by the appended claims.

I claim:

1. A lift assembly for vertical movement of an annular object, theassembly comprising:

a plate element of a configuration to fit within the annular object, theplate element having opposite sides;

the plate element having a central opening therein with a sleeve fixedin the opening;

a rod mounted slidably within the sleeve, the rod having hoistconnection means at one end and sleeve engagement means at its oppositeend;

a plurality of equidistantly spaced, radially arranged horizontalsleeves fixed on one of the side of the plate element, the horizontalsleeves having slide ways therein;

extendable and retractable engagement bars disposed slidably in theslide Ways of the horizontal sleeves and extendabl'e" therefrom topositions wherein they project outwardly of the plate and retractable topositions within the area of the plates;

the engagement bars having inner ends with angle bars thereomand r p apair of lugs on theplate adjacent .each of the horizontal sleeves, eachpair including a reduced width lug contactedby one ofthe angle bars whenthe engagement bars are in saidextended positions, and wide lugscontacted by the angle bars when the engagement bars are retracted.

2. Theinventionof'claim 1, wherein:

the horizontal sleeves are mounted on the upper side of the plateelement; and

a gusset plate secured to the lower side of the plate element and to thevertical sleeves below each of the horizontal sleeves.

References Cited I UNITED STATES PATENTS 678,416 7/1901 Bell 294-931,266,653 5/1918 Barlow 29493 1,717,006 6/1929 Cartwright 294932,471,323 5/1949 Harrington 29493 2,759,757 8/ 1956 Pace 29493 2,809,07010/1957 Nelson 29493 3,206,243 9/ 1965 Miles 29493 EDWARD A. SROKA,Primary Examiner.

H. C. HORNSBY, Assistant Examiner.

